Initial investigation into the metabolic effects of intra-articular betamethasone on normal and insulin dysregulated horses.
Authors: Page A E, Rauber-Ramos A M, Humiston M, McPeek J L, Adam E N
Journal: Journal of equine veterinary science
Summary
# Editorial Summary Intra-articular corticosteroid injections are routine in equine practice, yet their systemic metabolic consequences remain incompletely characterised—particularly in insulin dysregulated horses, which are already prone to glucose dysmetabolism. Page and colleagues investigated whether a standard 9 mg betamethasone injection into the metacarpophalangeal joints produced measurable changes in ACTH, cortisol, insulin and glucose in five metabolically normal and three insulin dysregulated geldings, employing a crossover design with saline controls and serial blood sampling over 48 hours plus oral sugar tolerance testing. Betamethasone suppressed both ACTH and cortisol significantly through 24–48 hours in both groups, whilst non-dysregulated horses showed significant post-injection hyperglycaemia between 8–48 hours; insulin response patterns could not be reliably evaluated due to the small cohort size. For practitioners managing joint disease in metabolically compromised horses—particularly those with equine metabolic syndrome or equine insulin dysregulation—these preliminary findings suggest IA betamethasone may transiently impair glucose tolerance, though larger studies are required to establish whether this translates to clinically meaningful risk or altered dosing protocols in susceptible individuals.
Read the full abstract on PubMed
Practical Takeaways
- •IA betamethasone injections suppress systemic cortisol and ACTH for 24-48 hours; clinicians should consider timing of diagnostic tests when evaluating horses post-injection
- •Horses with insulin dysregulation may respond differently to IA betamethasone than metabolically normal horses—monitor glucose and metabolic status more carefully in ID horses receiving joint injections
- •This pilot study is underpowered and preliminary; larger investigations are needed before changing clinical practice protocols for IA corticosteroid use in metabolically compromised horses
Key Findings
- •Intra-articular betamethasone (9 mg) suppressed ACTH and cortisol in both insulin dysregulated and non-dysregulated horses through 24-48 hours post-injection
- •Non-insulin dysregulated horses showed significant glucose elevation between 8-48 hours post-betamethasone administration
- •Insulin dysregulated horses did not demonstrate significant changes in measured parameters, though the study was underpowered for insulin analysis
- •Oral sugar testing was performed pre- and post-administration but specific results were not detailed in the abstract